Reproducing apparatus having high-speed reproducing function

ABSTRACT

In a reproducing apparatus, a plurality of pictures of image data reproduced from a recording medium at a speed higher than a normal reproduction speed is stored in a memory, each of the plurality of pictures of image data stored in the memory is divided into a plurality of regions, and one picture of image data is formed by using the different divided regions of the plurality of pictures of image data.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a reproducing apparatus and, moreparticularly, to processing of image data when the image data isreproduced at a high rate.

2. Related Background Art

This type of apparatuses for recording moving image data in a digitalform on a recording medium such as a tape or a disk are known.

In recent years, particularly, significant progress has been made inincreasing the storage capacity of disk mediums, and apparatuses havebeen proposed which perform long-time recording and reproducing of videosignals as well as audio signals on and from a disk medium. For example,techniques using recording formats based on high-efficiency codingsystems proposed by the Moving Picture Experts Group (MPEG), etc., arebeing studied to realize a picture recording/reproducing apparatus forone hour or longer at a data rate of about 4 to 10 Mbps. Further, thereis also a positive trend in the development of disk mediums per setoward smaller disk mediums having larger capacities. The development ofapparatuses capable of recording and reproduction at higher densities isbeing advanced.

In apparatuses for performing recording and reproduction on and from adisk medium, a search (special reproduction) may also be performed forthe purpose of identifying the contents of a recording on the recordingmedium, as in conventional video tape recorders. To search moving imagedata recorded on a disk medium, the data is reproduced by determining anamount of feed of tracks on the recording medium according to a setreproduction speed (set by a user, for example) and the user checksreproduced images through a television monitor, an liquid crystaldisplay monitor, or the like. The reproduction speed during searchreproduction is determined by this track feed amount.

Such a search reproduction function conceived in the conventional art,however, is to update displayed images on frame basis at time intervalsaccording to its reproduction speed and therefore entails a drawback inthat the movements of the search reproduction images are intermittentand lack smoothness when a scene is changed and when a scene has largemovement. Thus, there has been the problem in that checking of imagecontents during search reproduction requires a great deal of user'scontinuous attention to displayed images changing rapidly on a framebasis, and that images reproduced to be checked is of considerablyinferior quality because of their lack of smoothness in motion and theirdiscontinuous and fragmentary condition.

SUMMARY OF THE INVENTION

In view of the above-described circumstances, an object of the presentinvention is to provide a reproducing apparatus capable of obtaining areproducing image having a smooth movement even at the time ofhigh-speed reproduction.

To achieve this object, according to an aspect of the present invention,there is provided a reproducing apparatus comprising reproducing meansfor reproducing image data from a recording medium at a speed higherthan a normal reproduction speed, storage means for storing a pluralityof pictures of image data reproduced by the reproducing means, andforming means for dividing each of a plurality of pictures of image datastored in the storage means into a plurality of regions and for formingone picture of high-speed-reproduction image data by using the differentdivided regions of the plurality of pidtures of image data.

These and other objects and features of the present invention willbecome more apparent from the detailed description of embodiments of theinvention with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing the configuration of a recording system of arecording and reproducing apparatus to which the present invention isapplied;

FIG. 2 is a diagram showing the configuration of a reproducing system ofthe recording and reproducing apparatus to which the present inventionis applied;

FIG. 3 is a diagram for explaining coding processing in the apparatusshown in FIG. 1;

FIG. 4 is a diagram showing the configuration of a coding circuit in thesystem shown in FIG. 2;

FIG. 5 is a diagram for explaining the operation at the time of searchreproduction in an embodiment of the present invention;

FIG. 6 is a diagram showing a reproduced image at the time of searchreproduction in the embodiment of the present invention; and

FIG. 7 is a flowchart for explaining another search reproductionoperation in the embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the present invention will be described with reference tothe accompanying drawings.

FIG. 1 is a block diagram showing the configuration of a recordingsystem 100 of a recording and reproducing apparatus to which the presentinvention is applied, and FIG. 2 is a block diagram showing theconfiguration of a reproducing system 200 of the apparatus.

The recording operation of the apparatus showing in FIG. 1 will first bedescribed.

Referring to FIG. 1, image data obtained by an image pickup unit 101 isconverted into a digital signal by a camera signal processing circuit102, and the converted signal undergoes various kinds of signalprocessing such as gain adjustment, color separation, gradationcorrection, white balancing, etc.

The image signal thus obtained is temporarily stored in a memory 103. Inthis embodiment, frames of image data are each separated into threekinds of pictures: “intra picture (I-picture)”, “predictive picture(P-picture)”, and “bidirectionally predictive picture (B-picture)”according to the modes in which they are coded. These pictures are eacharranged in such a manner that one I-picture is placed as a leadingpicture, P-pictures are each placed as every third frame after theI-picture, and two frames of B-pictures are placed before and after eachP-picture, and thus form a group of pictures (GOP) composed of a totalof 15 frames. The pictures thus arranged are rearranged by changing theorder in which the pictures are each output from the memory 103. The GOPis a basic unit used in coding in accordance with an MPEG system.

This rearrangement will be explained below with reference to FIG. 3.

Coding in this embodiment, for example, interframe coding is performedby arranging P-frames as every third frame after one I-frame ofintra-frame and interposing two B frames between the I- and P-frames.

If an image input to the memory 103 has frames Bzn−1, Bzn, Ia0, Ba0,Ba1, Ba2, Pa0, Ba2, Ba3, Pa1 . . . as represented by a group of frames301 in FIG. 3, and if the frames are processed in the input order to becoded into B-, B-, I-, B-, B-, P-, B-, B-, P- . . . frames, the memory103 outputs image data in the order of Ia0, Bzn−1, Bzn, Pa0, Ba0, Ba1,Pa1, Ba2, Ba3 . . . , as represented by a group of frames 302 in FIG. 3.

Image data output from the memory 103 is supplied to a terminal a of twoterminals a and b of a switch 106, to a subtracter 107 and to a motioncompensation prediction circuit 120.

To process image data input as shown in FIG. 3, frame Ia0 of image datafrom the memory 103 is first read out on a k×1 (e.g., 8×8) pixel blockbasis to be supplied to the terminal a of the switch 106 and to thesubtracter 107.

When the image data output from the memory 103 is an I-frame, the switch106 selects the terminal a. When the image output from the memory 103 isa P- or B-frame, the switch 106 selects the terminal b. At this stage,therefore, the switch 106 selects the terminal a to supply frame Ia0 ofimage data in the form of blocks to a discrete cosine transform (DCT)circuit 104.

The DCT circuit 104 converts the image data supplied from the switch 106into data in a frequency region by DCT processing with respect to 8×8pixel blocks, and supplies the converted data to a quantization circuit105.

The quantization circuit 105 quantizes the image data converted intodata in a frequency region by the DCT circuit 104 and supplies thequantized data to a variable length coding circuit 108 and to an inversequantization circuit 115. The variable length coding circuit 108 encodesthe quantized data supplied from the quantization circuit 105 byvariable length coding such as run-length coding or the like andsupplies the encoded data to a multiplexing circuit 109.

On the other hand, the inverse quantization circuit 115inverse-quantizes the data supplied from the quantization circuit 105and supplies the inverse-quantized data to an inverse DCT circuit 116.The inverse DCT circuit 116 processes, by inverse DCT processing, theimage data supplied from the inverse quantization circuit 115 to convertthe data in a frequency region into data in a two-dimensional-spaceregion, and supplies the converted data to an addition circuit 117.

The addition circuit 117 adds data from a switch 119 to the dataprocessed by inverse DCT and supplied from the inverse DCT circuit 116.The switch 119 selects a terminal b to supply data 0 to the additioncircuit 117 when I-frame image data is output from the inverse DCTcircuit 116. At this time, therefore, data having substantially the samevalues as that before being coded is output as decoded data from theaddition circuit 117 to be supplied to a memory 118. The memory 118stores the supplied decoded data at a predetermined address.

After the completion of coding of frame Ia0, the memory 103 reads outframes Bzn−1 and Bzn of image data in this order to process theseframes. Processing of these frames is the same as processing of framesBa0 and Ba1 and will be described in detail by the description ofprocessing of frames Ba0 and Ba1 described below.

Next, the memory 103 reads out frame Pa0 of image data on a k×1 pixelblock basis and supplies the read data to the subtracter 107 and to themotion compensation prediction circuit 120. The motion compensationprediction circuit 120 obtains a motion vector of data (block) havingthe least prediction error (difference) by searching frame Ia0 of imagedata decoded and stored in the memory 118. The motion compensationprediction circuit 120 reads out from the memory 118 the decoded datadesignated by the motion vector as a predicted data, supplies this datato the subtracter 107 and to the switch 119, and outputs the obtainedmotion vector to a motion detection circuit 121.

The subtracter 107 computes the difference between the frame Pa0 ofimage data supplied from the memory 103 and the predicted data read outfrom the memory 118 and supplied to the subtracter 107 by the motioncompensation circuit 120, and supplies the computation result to theother terminal b of the switch 106. The switch 106 selects the terminalb and supplies the output from the subtracter 107 to the DCT circuit 104when the image data supplied from the memory 103 is a P- or B-frame. TheDCT circuit 104 converts the data in a spatial region from the switch106 into data in a frequency region by DCT, and outputs the converteddata to the quantization circuit 105. The quantization circuit 105quantizes the data converted by DCT and supplied from the DCT circuit104 and supplies the quantized data to the variable length codingcircuit 108 and to the inverse quantization circuit 115.

The variable length coding circuit 108 encodes the quantized datasupplied from the quantization circuit 105 by variable length coding andsupplies the encoded data to the multiplexing circuit 109. The inversequantization circuit 115 inverse-quantizes the data supplied from thequantization circuit 105 and supplies the inverse-quantized data to theinverse DCT circuit 116. The inverse DCT circuit 116 processes byinverse DCT the data supplied from the inverse quantization circuit 115to convert the data on the frequency axis into data in atwo-dimensional-space region, and supplies the converted data to theaddition circuit 117.

The addition circuit 117 adds data from the switch 119 to the dataprocessed by inverse DCT and supplied from the inverse DCT circuit 116.Here, the switch 119 is in the state of selecting the terminal a andoutputs to the addition circuit 117 the data predicted from frame Ia0and read out from the memory 118 by the motion compensation predictioncircuit 120 as described above. The addition circuit 117 adds thispredicted data to the data converted by inverse DCT and supplied fromthe inverse DCT circuit 116, and supplies the addition result as decodeddata to the memory 118. The memory 118 stores at a predetermined addressthe decoded data supplied from the addition circuit 117.

After the completion of coding of frame Pa0 of image data, the motiondetection circuit 121 obtains the total sum of the absolute values ofmotion vectors of one frame supplied from the motion compensationprediction circuit 120, binarizes the total sum by using a predeterminedthreshold value to obtain 1-bit frame motion information, and suppliesthis information to the CPU 122.

An operation switch 123 has an operating key for instructing start andstop of recording, and changes modes in which the apparatus operates bysending to the CPU 122 a control signal as an instruction to start orstop recording according to the operation of the operating key. The CPU122 transmits the motion information from the motion detection circuit121 to the multiplexing circuit 109.

The multiplexing circuit 109 multiplexes, on the variable-length-codeddata supplied from the variable length coding circuit 108, the motionvectors from the motion compensation prediction circuit 120, andadditional information, such as header information, motion information,and scene change information, supplied from the CPU 122.

For example, the motion information is multiplexed as additionalinformation to form a header in each frame of coded data.

After the completion of coding of frame Pa0, the memory 103 next readsout frame Ba0 and the same processing as that of frame Pa0 is performed.The motion compensation prediction circuit 120 can perform predictionfrom both frames Ia0 and Pa0 stored as decoded data in the memory 118.After the completion of coding of frame Ba0, the motion detectioncircuit 121 obtains the total sum of the absolute values of motionvectors supplied from the motion compensation prediction circuit 120 andsupplies the total sum as frame motion information to the CPU 122. Themultiplexing circuit 109 multiplexes on the variable-length-coded datatrain of frame Ba0 the motion vectors from the motion compensationprediction circuit 120 and the motion information from the CPU 122.

Frame Ba1 is processed in the same manner as frame Ba0, followed byprocessing of frame Pa1. In processing of frame Pa1, however, the motioncompensation prediction circuit 120 performs prediction from the decodeddata on frame Pa0 to obtain motion vectors and supplies the motionvectors to the motion detection circuit 121 and to the multiplexingcircuit 109. After the completion of coding of frame Pa1 of image data,the motion detection circuit 121 obtains the total sum of the absolutevalues of the motion vectors supplied from the motion compensationprediction circuit 120 and supplies the obtained total sum as framemotion information to the CPU 122. The multiplexing circuit 109multiplexes on the variable-length-coded data train of frame Pa0 themotion vectors from the motion compensation prediction circuit 120 andthe motion information from the CPU 122.

The multiplexing circuit 109 supplies an error correcting circuit 110with multiplexed data in which the motion vectors, the motioninformation and the coded image data are multiplexed as described above.The error correcting circuit 110 processes the data output from themultiplexing circuit 109 by error correcting coding suitable for amagneto-optical disc 113 and outputs the processed data to a buffer 111.The buffer 111 buffers recording data according to the amount ofinformation in the recording data and outputs the buffered data to arecording circuit 112. The recording circuit 112 is constituted of awell-known light beam irradiation section, a drive section for driving amagnetic head and the disc 113, etc., and records the data output fromthe buffer 111 on the magneto-optical disc 113.

Thereafter, frames Ba2 and Ba3 are successively processed in this orderand recorded on the disc 113.

A reproducing system 200 will now be described with reference to FIG. 2.

The operation at the time of normal reproduction will first bedescribed.

Referring to FIG. 2, the operation switch 123 has a reproduction key forproviding an instruction to perform normal reproduction and a searchreproduction key for providing an instruction to perform searchreproduction described below. When the CPU 122 receives the normalreproduction instruction by the operation switch 123, it outputs acontrol signal to a reproducing circuit 201.

The reproducing circuit 201 has the light beam irradiation section, thedrive section, etc., used in the recording circuit 112 shown in FIG. 1.The reproducing circuit 201 reproduces, at a normal reproduction speed,data recorded on the magneto-optical disc 113, and outputs thereproduced data to a buffer 202. The buffer 202 buffers the reproduceddata according to the data rate of the reproduced data from themagneto-optical disc 113 and outputs the buffered data to an errorcorrecting circuit 203.

The error correcting circuit 203 corrects errors in the reproduced dataaccording to error correcting coding at the time of recording andoutputs the error-corrected reproduced data to a decoding circuit 204and to the CPU 122. The decoding circuit 204 decodes the reproducedimage data and outputs the decoded data to a memory 205.

FIG. 4 is a diagram showing the configuration of the decoding circuit204.

Referring to FIG. 4, reproduced data from the error correcting circuit203 is output to an inverse quantization circuit 401 and to a motioncompensation circuit 404. The inverse quantization circuit 401inverse-quantizes the reproduced data and outputs the inverse-quantizeddata to an inverse DCT circuit 402. The inverse DCT circuit 402processes the data from the inverse quantization circuit 401 by inverseDCT processing and outputs the processed data to an adder 403.

The adder 403 adds together data output from a switch 405 and the dataoutput from the inverse DCT circuit 402 and outputs the addition resultto the memory 205 and to the motion compensation circuit 404. The switch405 establishes a connection through a terminal b to select zero datawhen the reproduced data is an I-picture, and establishes a connectionthrough a terminal a to select the data output from the motioncompensation circuit 404 when the reproduced data is a P- or B-picture.

The motion compensation circuit 404 detects the picture type of thereproduced image data on the basis of the reproduced data from the errorcorrecting circuit 203 and stores in an internal memory the data outputfrom the adder 403 when the reproduced data is an I- or P-picture. Themotion compensation circuit 404 reads out the image data stored in theinternal memory on the basis of the motion vectors of each block in thereproduced data, and outputs the read image data to the switch 405.

The image data thus decoded by the decoding circuit 204 is stored in thememory 205. When the data is output from the memory 205, the orderthereof is changed.

That is, at the time of normal reproduction, the CPU 122 rearranges, inthe order shown by reference numeral 301 in FIG. 3, the reproduced datadecoded in the order indicated by reference numeral 302 in FIG. 3 andstored in the memory 205, and outputs the rearranged data. Thus, theorder of reproduced image data is changed by using the memory 205 and,accordingly, the memory 205 is capable of storing several frames (tenframes in this embodiment) of decoded image data.

The image data read out from the memory 205 is output to a buffer 207. Abuffer control circuit 209 reads out the image data stored in the buffer207 at a suitable timing according to an instruction from the CPU 122and outputs the read image data to an output circuit 208. Beforeoutputting the image data from the buffer 207, the output circuit 208processes the image data according to an external device to which thedata is to be output.

The operation at the time of search reproduction of the apparatus shownin FIG. 2 will next be described.

The recording and reproducing apparatus of this embodiment is capable ofreproducing recorded data from the disc 113 at a rate several timeshigher than the rate at which the data has been recorded on the disc 113by the recording system 100. Accordingly, recording in this embodimentis performed in such a manner that data is intermittently recorded onthe magneto-optical disc 113 each time a predetermined amount of data isstored in the buffer memory 111, and the data is intermittently read outfrom the disc 113 by the predetermined amount in the normal reproductionmode. At the time of search reproduction, the data is continuously readout from the magneto-optical disc 113. In this manner, the data isreproduced at a rate several times higher than the rate in the normalreproduction mode.

That is, referring to FIG. 2, when the search reproduction key of theoperation switch 123 is operated for instruction to perform theoperation in the search reproduction mode, the CPU 122 controls thereproducing circuit 201 to reproduce data at a speed several timeshigher, five times higher in this embodiment than the speed in thenormal reproduction mode, and to output the reproduced data to the errorcorrecting circuit 203 via the buffer 202. The reproducing system 200 iscapable of processing reproduced data at a speed five times higher thanthe speed in the normal reproduction mode, and the decoding circuit 204decodes all the data reproduced at the speed five times higher than thespeed in the normal reproduction mode and outputs the decoded data tothe memory 205.

Here, the concept on which processing of output data at the time ofquintuple-speed search reproduction in this embodiment is based will bedescribed with reference to FIG. 5.

Quintuple-speed search reproduction may be achieved by outputting fiveframes of image data during the time period corresponding to one frame.In this embodiment, therefore, all the data recorded at a speed fivetimes higher than the normal reproduction speed are reproduced anddecoded at the time of search reproduction. FIG. 5 shows a state ofreproduced image data and a displayed image. In FIG. 5, each of sections501, 502, and 503 includes a group of successive five frames of imagedata, and the combination of these groups of frames 501, 502, and 503,that is, 15 frames of image data form GOP1.

As shown in FIG. 5, the group of successive five frames of image 501 inthe 15 frames of image data in one reproduced GOP is used to form oneframe of image data 504, the group of successive five frames of image502 is used to form one frame of image data 505, and the group ofsuccessive five frames of image 503 is used to form one frame of imagedata 506.

The area of each frame of image data is divided into five regions, andfive divided regions of the five frames at different positions are usedto form one frame of image data.

FIG. 6 shows the process of forming one frame of image data fromsuccessive five frames of image data.

As shown in FIG. 6, image data of each of successive five frames C1, C2,C3, C4, and C5 indicated at 601 is divided into five regions 601 a, 601b, 601 c, 601 d, and 602 e. One of the five divided regions of eachframe is extracted as shown at reference numeral 602, and image dataunits corresponding to the extracted regions of the five frames arecombined to form one image frame as shown at reference numeral 603.

That is, a region C1 a corresponding to 1st to 96th lines from the topis extracted from frame C1, a region C2 b corresponding to 97th to 192ndlines from frame C2, a region C3 c corresponding to 193rd to 288th linesfrom frame C3, a region C4 d corresponding to 289th to 384th lines fromframe C4, and a region C5 e from 385th to 480th lines from frame C5, andthese regions are placed in this order from the top, as shown atreference numeral 603.

Thus, a plurality of successive frames of image data are each dividedinto a plurality of regions, and the parts of the regions of each frameare combined to form one frame of image data for images to be searched.As a result, each of the frame images output at the time of searchreproduction can change smoothly.

Specifically, referring to FIG. 2, the CPU 122 reads out image data onone of divided five regions of each of five frames of image dataappearing successively as shown in FIGS. 5 and 6 in a plurality offrames of reproduced image data stored in the memory 205, and outputsthe read image data to the buffer 207. Then the CPU 122 controls thebuffer control circuit 209 to determine an address in the buffer 207 atwhich image data on each region read out from the memory 205 is stored,such that one frame of image data is formed as shown at 603 in FIG. 6.The buffer control circuit 209 reads out the thus-formed frames of imagedata to be searched one by one at intervals of 1/30 sec, and supplieseach frame to the output circuit 208.

Thus, at the time of quintuple-speed search reproduction in thisembodiment, all the data are reproduced from the disc at a speed fivetimes higher than the normal reproduction speed, and portions of fivesuccessive frames of image data reproduced at the quintuple speeddivided into a plurality of regions are combined to form one frame ofimage data to be searched, thereby enabling even images reproducedduring search reproduction to be obtained as smoothly moving images.

Consequently, the present invention realizes search reproductionensuring improved visibility in comparison with the conventional methodof updating displayed images on a frame basis.

A second embodiment of the present invention will now be described.

The configuration of the recording and reproducing apparatus in thisembodiment is the same as that shown in FIGS. 1 and 2. In thisembodiment, a search is performed by using motion information withrespect to frames, which is formed by the motion detection circuit 121shown in FIG. 1 and recorded together with image data.

The search reproduction operation in this embodiment will be describedwith reference to the flowchart of FIG. 7.

Referring to FIG. 7, when the operation switch 123 is operated to inputan instruction to start search reproduction, the CPU 122 performsquintuple-speed read-out by controlling the reproducing circuit 201 asdescribed above to reproduce data from the disc 113 at a speed fivetimes higher than the normal reproduction speed (S701). The CPU 122 thendetects, from the reproduced data from the error correcting circuit 203,motion information with respect to frames added at the time of recordingto determine whether there is a movement. In this embodiment, theexistence of a movement is recognized if one GOP contains eight or moreframes to which motion information indicating the existence of amovement has been added (S702).

If the existence of a movement is recognized as in the above-mentionedembodiment, successive five frames of image data stored in the memory205 is divided into a plurality of regions, a region to be displayed isselected from each frame (S703), and the selected region of the data isoutput to the buffer 207 (S704).

On the other hand, if it is determined in step S702 that there is nomovement, a search-object image formed by the above-described synthesisprocessing is output from the image data on the present GOP but only theleading I-picture is selected and output to the buffer 207 with respectto the next GOP (S706). Then the buffer control circuit 209 iscontrolled so as to continuously output this leading I-picture for the3-frame period. This process is repeated until an instruction to stopsearch reproduction is given (S705).

Thus, in this embodiment, only an I-pictures is output when a reproducedimage does not move largely. Therefore, an image higher in resolutionthan an image formed by combining portions of five frames of image dataas shown in FIG. 6 can be output. In this case, an image formed of thesame I-picture is output for the period corresponding to one GOP inreproduced data, i.e., the 3-frame period during quintuple-speed searchreproduction. However, since the original recorded image has only asmall movement, the output image is generally satisfactory in terms ofnaturalness.

Since portions of five successive frames of image data are combined toform a search-object image if the extent of movement is large, asmoothly moving search-object image can be obtained.

The embodiments of the present invention have been described withrespect to case where, in consideration of reproducible data rate,memory capacity or the like, the reproduction speed during searchreproduction is set to a speed five times higher than the normalreproduction speed. However, the ability of the recording andreproducing system and the memory capacity may be changed as desired toperform search reproduction at a speed other than the above-mentionedspeed.

For example, in a case where tenfold-speed reproduction is performed,the arrangement may be such that data is reproduced from disc 113 at aspeed ten times higher than the normal reproduction speed, each ofsuccessive ten frames stored in the memory is divided into ten regions,and respective portions of the ten frames of reproduced image data arecombined to form one frame of image data for tenfold-speed search, asshown in FIG. 6.

That is, to perform n-fold-speed reproduction, each of n frames of imagedata successively reproduced is divided into n regions, and one regionis extracted from each frame to form one frame. In this manner, imagescan be reproduced to be searched with the same facility.

While the embodiments of the present invention have been described withrespect to an apparatus which compresses, encodes and record image dataon the basis of an MPEG system, the present invention can beadvantageously applied to recording and production of image data on adisk medium on the basis of other systems to achieve similar effects.

Many widely different embodiments of the present invention may beconstructed without departing from the spirit and scope of the presentinvention. It should be understood that the present invention is notlimited to the specific embodiments described in the specification,except as defined in the appended claims.

1. A reproducing apparatus comprising: reproducing means for reproducingimage data from a recording medium, said reproducing means reproducingthe image data at a speed higher than a normal reproduction speed in ahigh-speed reproduction mode; storage means for storing a plurality ofpictures of image data reproduced by said reproducing means; and formingmeans for dividing each of a plurality of pictures of image data storedin said storage means into a predetermined number of regionscorresponding to the speed at which the image data is reproduced in saidhigh-speed reproduction mode, and for forming one picture ofhigh-speed-reproduction image data by using the different dividedregions of the plurality of pictures of image data.
 2. An apparatusaccording to claim 1, wherein said forming means divides each of aplurality of successive pictures of image data stored in said storagemeans into a plurality of regions, and forms one picture ofhigh-speed-reproduction image data by using one of divided regions ofeach of the plurality of pictures of image data, said one divided regionof each picture differing in position from each other.
 3. An apparatusaccording to claim 1, wherein said forming means divides each of npictures (n: an integer equal to or greater than 2) of image data storedin said storage means into a plurality of regions, and forms one frameof high-speed-reproduction image data by using one of n divided regionsof each of the plurality of pictures of image data, said one dividedregion of each picture differing in position from each other.
 4. Anapparatus according to claim 3, wherein said forming means forms onepicture of the high-speed-reproduction image data for every nth pictureof image data reproduced by said reproducing means.
 5. An apparatusaccording to claim 3, wherein the number n is determined according tothe speed at which the image data is reproduced by said reproducingmeans.
 6. An apparatus according to claim 1, wherein the image data isencoded by interpicture coding and by intrapicture coding.
 7. Anapparatus according to claim 6, wherein said reproducing means hasdecoding means for decoding the reproduced image data, and said storagemeans stores image data decoded by said decoding means.
 8. An apparatusaccording to claim 1, wherein the recording medium comprises a disc-likerecording medium.
 9. A reproducing apparatus comprising: reproducingmeans for reproducing image data from a recording medium, saidreproducing means being arranged to reproduce the image data atdifferent reproduction speeds; storage means for storing a plurality ofpictures of image data reproduced by said reproducing means; and formingmeans for forming normal-reproduction image data and search-reproductionimage data by using the plurality of pictures of image data stored insaid storage means, said forming means forming one picture of thenormal-reproduction image data by using only one picture of image datain the plurality of pictures of image data stored in said storage means,said forming means dividing each of a plurality of pictures of imagedata stored in said storage means into a predetermined number of regionscorresponding to higher one of the different reproduction speed at whichthe image data is reproduced, and for forming one picture of thesearch-reproduction image data by using the different divided regions ofthe plurality of pictures of image data; and mode change means forchanging the reproduction mode between a normal reproduction mode inwhich said reproducing means reproduces the image data at a normalreproduction speed and said forming means forms the normal-reproductionimage data, and a search reproduction mode in which said reproducingmeans reproduces the image data at a speed higher than the normalreproduction speed and said forming means forms the search-reproductionimage data.
 10. An apparatus according to claim 9, wherein said formingmeans divides each of a plurality of successive pictures of image datastored in said storage means into a plurality of regions, and forms onepicture of search-reproduction image data by using one of dividedregions of each of the plurality of pictures of image data, said onedivided region of each picture differing in position from each other.11. An apparatus according to claim 9, wherein said forming meansdivides each of n pictures (n: an integer equal to or greater than 2) ofimage data stored in said storage means into a plurality of regions, andforms one frame of search-reproduction image data by using one of ndivided regions of each of the plurality of pictures of image data, saidone divided region differing of each picture in position from eachother.
 12. An apparatus according to claim 11, wherein said formingmeans forms one picture of the search-reproduction image data for everynth picture of image data reproduced at a speed higher than thenormal-reproduction speed.
 13. An apparatus according to claim 11,wherein the number n is determined according to the speed at which theimage data is reproduced in the search reproduction mode.
 14. Anapparatus according to claim 9, wherein the image data is encoded byinterpicture coding and by intrapicture coding.
 15. An apparatusaccording to claim 14, wherein said reproducing means has decoding meansfor decoding the reproduced image data, and said storage means storesimage data decoded by said decoding means.
 16. An apparatus according toclaim 9, wherein the recording medium comprises a disc-like recordingmedium.
 17. A reproducing apparatus comprising: reproducing means forreproducing image data from a recording medium; storage means forstoring a plurality of pictures of image data in the image datareproduced by said reproducing means; mode change means for changing thereproduction mode between a first reproduction mode and a secondreproduction mode according to motion of an image relating to the imagedata reproduced by said reproducing means; and forming means for formingfirst image data and second image data by using the plurality ofpictures of image data stored in said storage means, said forming meansdividing each of a plurality of pictures of image data stored in saidstorage means into a plurality of regions, said forming means formingone picture of the first image data by using the different dividedregions of the plurality of pictures of image data, said forming meansforming one picture of the second image data by using only one pictureof image data of the plurality of pictures of image data stored in saidstorage means, said forming means firming the first image data in thefirst reproduction mode and forming the second image data in the secondreproduction mode, wherein said reproducing means also reproduces motioninformation indicating a movement of an image relating to the image datarecorded on the recording medium, and said mode change means changes thereproduction mode according to the motion information reproduced by saidreproducing means.
 18. An apparatus according to claim 17, wherein theimage data reproduced by said reproducing means is encoded byinterpicture coding and by intrapicture coding, and said reproducingmeans has decoding means for decoding the image data reproduced from therecording medium.
 19. An apparatus according to claim 18, wherein saidstorage means stores the image data decoded by said decoding means, andsaid forming means forms, in the second mode, one picture of the firstimage data by using only decoded image data of the image data encoded byintrapicture coding.
 20. A reproducing apparatus comprising: reproducingmeans for reproducing image data from a disc-like recording medium; andforming means for dividing each of a plurality of pictures of image datareproduced by said reproducing means in a search reproduction mode inwhich said reproducing means reproduces the image data at a speed higherthan a normal reproduction speed into a predetermined number of regionscorresponding to the speed at which the image data is reproduced in saidsearch reproduction mode, and for forming one picture ofsearch-reproduction image data by using the different divided regions ofthe plurality of pictures of image data.
 21. An apparatus according toclaim 20, wherein the image data recorded on the disc-like recordingmedium is encoded by interpicture coding and by intrapicture coding, andsaid forming means forms, in the search reproduction mode, one pictureof the search-reproduction image data by using portions of the pluralityof successive pictures of image data including image data decoded fromthe intrapicture-coded image data and image data decoded from theinterpicture-coded image data in the image data reproduced by saidreproducing means.
 22. A method for reproducing image data from arecording medium, said method comprising the steps of: storing in amemory a plurality of pictures of image data reproduced from therecording medium at a speed higher than a normal reproduction speed in ahigh-speed reproduction mode; and dividing each of the plurality ofpictures of image data stored in the memory into a predetermined numberof regions corresponding to the speed at which the image data isreproduced in said high-speed reproduction mode, and for forming onepicture of image data by using the different divided regions of theplurality of pictures of image data.
 23. A reproduction methodcomprising the steps of: reproducing image data from a disc-likerecording medium; and dividing each of a plurality of pictures of imagedata reproduced by said reproducing means in a search reproduction modein which said reproducing means reproduces the image data at a speedhigher than a normal reproduction speed into a predetermined number ofregions corresponding to the speed at which the image data is reproducedin said search reproduction mode, and forming one picture ofsearch-reproduction image data by using the different divided regions ofthe plurality of pictures of image data.